Field of the Invention
The invention relates to a fuel injection valve having a control chamber that is connected to an inflow duct. A pressure in the control chamber is operatively connected to a nozzle needle and the pressure in the control chamber controls the nozzle needle. A servovalve having a closing body and an associated valve seat is disposed between the control chamber and a return duct. In a closed position, in which the closing body is moved by an actuator, the closing body closes an outflow of the fuel injection valve.
Such a fuel injection valve is known from Published, European Patent Application EP 0 816 670 A1. The known fuel injection valve contains a servovalve which serves for bringing about hydraulically the opening and closing of the fuel injection valve, in particular for defining the start and end of the injection operation exactly in time. A spherical closing body is introduced in the valve chamber of the servovalve and is operatively connected to an actuator via a tappet. The closing body, together with a conical first valve seat of the valve chamber, forms a seal resistant to high pressure. When the actuator is deflected, the closing body is lifted off from the first valve seat, with the result that the servovalve opens (2/2-way valve). In another embodiment, a further conical sealing seat located opposite the first valve seat in the axial direction is disposed in the valve chamber, and, when the actuator is in the deflected state, the closing body covers the further valve seat, thus giving rise to a hydraulic stop (3/2-way valve).